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1.
Behav Pharmacol ; 29(4): 379-384, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28777104

RESUMO

Accumulated data support a relationship between mood disorders and cellular plasticity and resilience, some suggesting relevance to autophagy. Our previous data show that pharmacological enhancement of autophagy results in antidepressant-like effects in mice. The current study was designed to further examine the effects of autophagy enhancement on mood by testing the effects of subchronic treatment with the mammalian target of rapamycin (mTOR) inhibitors and autophagy enhancers rapamycin and temsirolimus in a model for mania and in a model for antidepressant action, respectively. The results show that rapamycin reduced mania-like aggression and reward-seeking behaviors, with no effects on locomotion. Temsirolimus reduced depression-related immobility in the forced-swim test without effects on locomotion in the open field or on anxiety-related measures in the elevated plus maze. Taken together with our previous findings, these data support the notion that enhancing autophagy may have mood-stabilizing effects.


Assuntos
Afeto/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Sirolimo/farmacologia , Agressão/efeitos dos fármacos , Animais , Antidepressivos/farmacologia , Antimaníacos/farmacologia , Ansiedade/tratamento farmacológico , Transtornos de Ansiedade/tratamento farmacológico , Comportamento Animal/efeitos dos fármacos , Depressão/tratamento farmacológico , Transtorno Depressivo/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos ICR , Sirolimo/análogos & derivados
2.
J Interprof Care ; 30(2): 265-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26934068

RESUMO

This article describes an interprofessional collaborative research practice fellowship designed to foster the research skills of clinical faculty. The year-long fellowship was grounded in big data analysis and the triangle of informatics--knowledge, information, and data. Fellows were selected to include diverse perspectives, training, and knowledge but had limited experience in team science or being a member of an interprofessional research team. The underlying philosophy of the fellowship was experiential learning. Protected time and formal mentorship were necessary factors for developing the interprofessional research practice and the skills to participate in an interprofessional research team. We believe that this innovative interprofessional faculty research fellowship is a viable option for supporting scholarly activity and research collaboration. The findings could inform interprofessional clinical practice and be implemented for patient care. Engagement in interprofessional collaborative research and incorporation of the perspectives, knowledge and expertise of multiple professions, is a model to de silo knowledge creation.


Assuntos
Docentes/organização & administração , Relações Interprofissionais , Pesquisa/organização & administração , Comportamento Cooperativo , Bolsas de Estudo , Humanos , Autoeficácia , Fatores de Tempo
3.
Nutr Neurosci ; 18(8): 365-75, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26177275

RESUMO

OBJECTIVES: Anemia caused by nutritional deficiencies, such as iron and copper deficiencies, is a global health problem. Iron and copper deficiencies have their most profound effect on the developing fetus/infant, leading to brain development deficits and poor cognitive outcomes. Tissue iron depletion or chronic anemia can induce cellular hypoxic signaling. In mice, chronic hypoxia induces a compensatory increase in brain blood vessel outgrowth. We hypothesized that developmental anemia, due to iron or copper deficiencies, induces angiogenesis/vasculogenesis in the neonatal brain. METHODS: To test our hypothesis, three independent experiments were performed where pregnant rats were fed iron- or copper-deficient diets from gestational day 2 through mid-lactation. Effects on the neonatal brain vasculature were determined using quantitative real-time polymerase chain reaction to assess mRNA levels of angiogenesis/vasculogenesis-associated genes and GLUT1 immunohistochemistry to assess brain blood vessel density and complexity. RESULTS: Iron deficiency, but not copper deficiency, increased mRNA expression of brain endothelial cell- and angiogenesis/vasculogenesis-associated genes (i.e. Glut1, Vwf, Vegfa, Ang2, Cxcl12, and Flk1) in the neonatal brain, suggesting increased cerebrovascular density. Iron deficiency also increased hippocampal and cerebral cortical blood vessel branching by 62 and 78%, respectively. DISCUSSION: This study demonstrates increased blood vessel complexity in the neonatal iron-deficient brain, which is likely due to elevated angiogenic/vasculogenic signaling. At least initially, this is probably an adaptive response to maintain metabolic substrate homeostasis in the developing iron-deficient brain. However, this may also contribute to long-term neurodevelopmental deficits.


Assuntos
Anemia Ferropriva/sangue , Córtex Cerebral/irrigação sanguínea , Cobre/sangue , Cobre/deficiência , Hipocampo/irrigação sanguínea , Neovascularização Patológica/sangue , Anemia Ferropriva/complicações , Animais , Animais Recém-Nascidos , Córtex Cerebral/crescimento & desenvolvimento , Ceruloplasmina/metabolismo , Modelos Animais de Doenças , Feminino , Feto , Regulação da Expressão Gênica no Desenvolvimento , Hemoglobinas/metabolismo , Hipocampo/crescimento & desenvolvimento , Masculino , Neovascularização Patológica/etiologia , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
4.
BMC Health Serv Res ; 14: 563, 2014 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-25407745

RESUMO

BACKGROUND: Non-malignant chronic pain (NMCP) is one of the most common reasons for primary care visits. Pain management health care disparities have been documented in relation to patient gender, race, and socioeconomic status. Although not studied in relation to chronic pain management, studies have found that living in a rural community in the US is associated with health care disparities. Rurality as a social determinant of health may influence opioid prescribing. We examined rural and non-rural differences in opioid prescribing patterns for NMCP management, hypothesizing that distinct from education, income, racial or gender differences, rural residency is a significant and independent factor in opioid prescribing patterns. METHODS: 2010 National Ambulatory Medical Care Survey (NAMCS) data were examined using bivariate and multivariate techniques. NAMCS data were collected using a multi-stage sampling strategy. For the multivariate analysis performed the SPSS complex samples algorithm for logistic regression was used. RESULTS: In 2010 an estimated 9,325,603 US adults (weighted from a sample of 2745) seen in primary care clinics had a diagnosis of NMCP; 36.4% were prescribed an opioid. For US adults with a NMCP diagnosis bivariate analysis revealed rural residents had higher odds of having an opioid prescription than similar non-rural adults (OR = 1.515, 95% CI 1.513-1.518). Complex samples logistic regression analysis confirmed the importance of rurality and yielded that US adults with NMCP who were prescribed an opioid had higher odds of: being non-Caucasian (AOR =2.459, 95% CI 1.194-5.066), and living in a rural area (AOR =2.935, 95% CI 1.416-6.083). CONCLUSIONS: Our results clearly indicated that rurality is an important factor in opioid prescribing patterns that cannot be ignored and bears further investigation. Further research on the growing concern about the over-prescribing of opioids in the US should now include rurality as a variable in data generation and analysis. Future research should also attempt to document the ecological, sociological and political factors impacting opioid prescribing and care in rural communities. Prescribers and health care policy makers need to critically evaluate the implications of our findings and their relationship to patient needs, best practices in a rural setting, and the overall consequences of increased opioid prescribing on rural communities.


Assuntos
Analgésicos Opioides/uso terapêutico , Dor Crônica/tratamento farmacológico , Padrões de Prática Médica/estatística & dados numéricos , Prescrições/estatística & dados numéricos , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , Estados Unidos , Adulto Jovem
5.
Innov Pharm ; 14(1)2023.
Artigo em Inglês | MEDLINE | ID: mdl-38035311

RESUMO

Community forums are a valuable tool in engaging rural communities to address critical public health issues. Recognizing low levels of COVID-19 vaccine uptake in rural Minnesota communities and the critical public health threat that resulted, pharmacy faculty and Extension professionals from the University of Minnesota partnered with a diverse group of rural stakeholders to plan a series of six community forums to provide life-saving, evidence-based education about the COVID-19 vaccine. Each forum allowed trusted local community leaders, public health workers and healthcare providers to share information about the impact of COVID-19 in their communities. Data about the COVID-19 vaccines was provided, and community members were allowed to ask questions and voice their concerns about the virus and the vaccines. Virtual community forums allowed rural stakeholders to reach a diverse and geographically remote population while maintaining COVID-19 distancing requirements. Offering a safe, virtual space and immediate access to reliable and trusted place-based education allowed individuals an opportunity to get their vaccine questions answered immediately. Community forums can be conducted in rural communities as a direct communication tool to address critical public health issues such as vaccine hesitancy, and empower community members to make informed decisions in fighting against the COVID-19 pandemic.

6.
Am J Pharm Educ ; 86(10): ajpe8920, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35165094

RESUMO

The variability and complexity of course prerequisites across colleges and schools of pharmacy can result in barriers to admission. While prerequisites play an important role in the admissions process and assuring student preparation, requiring excessive prerequisites can create unnecessary challenges for applicants. Prospective students may choose not to apply to a particular pharmacy school or even enter the profession because they cannot complete all course prerequisites in time to apply. Extraneous prerequisites can also contribute to the cost of education and educational indebtedness, which can more adversely affect minority and disadvantaged students. Pharmacy programs should carefully examine their course prerequisite requirements and consider new ways to measure preparedness to attract a diverse and competent pool of applicants to the profession while also being more competitive with other health professions programs.


Assuntos
Educação em Farmácia , Farmácia , Humanos , Critérios de Admissão Escolar , Escolaridade , Estudantes
7.
Gen Comp Endocrinol ; 168(1): 149-59, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20417208

RESUMO

Thyroid hormone (TH) induces the dramatic morphological and physiological changes that together comprise amphibian metamorphosis. TH-responsive tissues vary widely with developmental timing of TH-induced changes. How larval tadpole tissues are able to employ distinct metamorphic programs in a developmental stage- and TH-dependent manner is still unknown. Recently, several proteins capable of transporting TH have been identified. TH action and metabolism occurs primarily intracellularly, highlighting the importance of TH transporters. We examined the hypothesis that TH transporter expression and tissue distribution play an important role in mediating TH-induced metamorphic events. Xenopus tropicalis homologs for known TH transporting OATP, MCT and LAT family proteins were identified and gene specific qRT-PCR primers were developed. Total RNA was extracted from tissues representing three unique developmental fates including: growth/differentiation (hind limb), death/resorption (gill, tail) and remodeling (brain, liver, kidney). For growing and resorbing tissues, results showed the general trend of low initial expression levels of MCT8 and MCT10 transporters, followed by a several-fold increase of expression as the tissue undergoes TH-dependent metamorphic changes. The expression pattern in remodeling tissues was less uniform: a general decrease in transporter expression was observed in the liver, while the kidney and brain exhibited a range of expression patterns for several TH transporters. Collectively, these developmental expression patterns are consistent with TH transporting proteins playing a role in the effects of TH in peripheral tissues.


Assuntos
Proteínas de Membrana Transportadoras/metabolismo , Hormônios Tireóideos/metabolismo , Animais , Encéfalo/metabolismo , Brânquias/metabolismo , Rim/metabolismo , Fígado/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Cauda/metabolismo , Xenopus , Proteínas de Xenopus/metabolismo
8.
Mol Cell Endocrinol ; 302(1): 99-107, 2009 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-19356628

RESUMO

We created a Thrsp (Spot 14 or S14) null mouse (Thrsp(tm1cnm)) to study the role of Thrsp in de novo lipid synthesis. The Thrsp null mouse exhibits marked deficiencies in de novo lipogenesis in the lactating mammary gland. We now report the Thrsp gene deletion affects body weight and glucose tolerance associated with increased insulin sensitivity. By post-natal day 150 the rate of first generation C57BL/6J backcross Thrsp null mouse weight gain slowed compared to wild type animals. This was due to changes in body fat mass. We studied mice backcrossed for 5 and 11 generations. The weight difference between the null and wild type adult mice diminished with progressive backcross generations. In conclusion the Thrsp gene is involved in the regulation of diet-induced obesity and deletion of Thrsp leads to an improvement in age associated glucose tolerance.


Assuntos
Dieta , Proteínas Nucleares/genética , Obesidade/genética , Fatores de Transcrição/genética , Animais , Peso Corporal , Feminino , Glucose/metabolismo , Metabolismo dos Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
9.
J Invasive Cardiol ; 31(9): 272-277, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31199349

RESUMO

Cadaveric tissue-perfusion models are well established in the fields of structural heart and peripheral vascular disease; however, less consideration has been given toward coronary artery disease despite comparable prevalence and morbidity. Two tissue-perfusion models were developed to address this need. The first, an intact heart model, allows simulation of percutaneous coronary interventional procedures. The second focuses upon isolated arteries, allowing quantification of simulated procedures. Both models were applied for clinical training and for investigations into medical device behavior. The manner of preparation facilitates access to clinically relevant disease, thus providing a platform to further research on coronary artery disease.


Assuntos
Cardiologia/educação , Doença da Artéria Coronariana/diagnóstico , Circulação Coronária , Vasos Coronários/patologia , Educação de Pós-Graduação em Medicina/métodos , Cadáver , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/fisiopatologia , Fluoroscopia , Humanos , Perfusão
10.
Endocrinology ; 149(10): 5155-61, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18556348

RESUMO

The Spot 14 (S14) gene is rapidly up-regulated by signals that induce lipogenesis such as enhanced glucose metabolism and thyroid hormone administration. Previous studies in S14 null mice show that S14 is required for normal lipogenesis in the lactating mammary gland, but not the liver. We speculated that the lack of a hepatic phenotype was due to the expression of a compensatory gene. We recently reported that this gene is likely an S14 paralog that we named S14-Related (S14-R). S14-R is expressed in the liver, but not in the mammary gland. If S14-R compensates for the absence of S14 in the liver, we hypothesized that, like S14, S14-R expression should be glucose responsive. Here, we report that hepatic S14-R mRNA levels increase with high-carbohydrate feeding in mice or within 2 h of treating cultured hepatocytes with elevated glucose. A potential carbohydrate response element (ChoRE) was identified at position -458 of the S14-R promoter. Deletion of or point mutations within the putative S14-R ChoRE led to 50-95% inhibition of the glucose response. Gel-shift analysis revealed that the glucose-activated transcription complex carbohydrate responsive element-binding protein/Max-like protein X (Mlx) binds to the S14-R ChoRE. Finally, S14-R glucose induction is completely blocked when a dominant-negative form of Mlx is overexpressed in primary hepatocytes. In conclusion, our results indicate that the S14-R gene is a glucose-responsive target of carbohydrate responsive element-binding protein/Mlx and suggest that the S14-R protein is a compensatory factor, at least partially responsible for the normal liver lipogenesis observed in the S14 null mouse.


Assuntos
Carboidratos da Dieta/farmacologia , Fígado/fisiologia , Proteínas Nucleares/genética , Proteínas/genética , Fatores de Transcrição/genética , Animais , Células Cultivadas , Gorduras na Dieta/farmacologia , Feminino , Glucose/metabolismo , Hepatócitos/citologia , Hepatócitos/fisiologia , Lipogênese/fisiologia , Fígado/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Proteínas Nucleares/metabolismo , Gravidez , Regiões Promotoras Genéticas/fisiologia , Proteínas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição/metabolismo , Transfecção , Ubiquitina-Proteína Ligases
11.
Cerebellum ; 7(1): 60-74, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18418681

RESUMO

Thyroid hormone (TH) plays a key role in mammalian brain development. The developing brain is sensitive to both TH deficiency and excess. Brain development in the absence of TH results in motor skill deficiencies and reduced intellectual development. These functional abnormalities can be attributed to maldevelopment of specific cell types and regions of the brain including the cerebellum. TH functions at the molecular level by regulating gene transcription. Therefore, understanding how TH regulates cerebellar development requires identification of TH-regulated gene targets and the cells expressing these genes. Additionally, the process of TH-dependent regulation of gene expression is tightly controlled by mechanisms including regulation of TH transport, TH metabolism, toxicologic inhibition of TH signaling, and control of the nuclear TH response apparatus. This review will describe the functional, cellular, and molecular effects of TH deficit in the developing cerebellum and emphasize the most recent findings regarding TH action in this important brain region.


Assuntos
Cerebelo/crescimento & desenvolvimento , Hormônios Tireóideos/fisiologia , Animais , Animais Geneticamente Modificados , Encéfalo/fisiologia , Cerebelo/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Hipotireoidismo/genética , Hipotireoidismo/fisiopatologia , Hipotireoidismo/psicologia , Inteligência/fisiologia , Mamíferos , Transtornos Mentais/genética , Camundongos , Mitocôndrias/fisiologia , Atividade Motora , Hormônios Tireóideos/deficiência , Hormônios Tireóideos/genética
12.
Am Heart J ; 152(4): 770-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16996857

RESUMO

BACKGROUND: The CREST trial demonstrated that after successful coronary stent implantation, the 6-month rate of target vessel revascularization (TVR) was similar (15.4% vs 16%, P = .90) for the 2 treatment groups, but restenosis rate was lower (22.0% vs 34.5%, P = .002) in cilostazol-treated patients. We sought to evaluate resource use, cost, and cost-effectiveness of cilostazol in CREST. METHODS: A total of 705 patients were randomized to cilostazol 100 mg twice daily (n = 354) versus placebo (n = 351) for 6 months. Resources included rehospitalizations, medications, and outpatient services. Costs were determined from the Medicare fee schedule. Cilostazol was priced at 1.64 dollars a day. Base-case cost and cost-effectiveness analysis was performed for the entire population using TVR as a measure of effectiveness. Sensitivity analysis was conducted among 526 patients because restenosis data were available only for this patient population. A bootstrap resample approach (5000 samples) was used to obtain confidence intervals for cost differences. RESULTS: For the entire population, costs of rehospitalizations, concomitant medications, outpatient tests, and physician or emergency department visits were lower during follow-up for cilostazol-treated patients. Overall, total 6-month follow-up costs remained 447 dollars lower for cilostazol (4178 dollars vs 4625 dollars), although this difference did not reach significance (95% CI -1458 dollars to 515 dollars). Cilostazol is likely a cost-saving strategy (similar rate of TVR and lower costs). Sensitivity analysis showed that cilostazol is likely a dominant strategy (lower restenosis rate and costs, 85% dominant, 88.9% <1000 dollars per restenosis averted). CONCLUSIONS: Treatment with cilostazol is likely a cost-saving or dominant strategy in patients with successful coronary bare metal stent implantation. Cilostazol may offer a low-cost alternative to restenosis prevention in patients who do not receive drug-eluting stents.


Assuntos
Reestenose Coronária/prevenção & controle , Estenose Coronária/terapia , Custos de Cuidados de Saúde , Recursos em Saúde/estatística & dados numéricos , Inibidores da Agregação Plaquetária/uso terapêutico , Stents , Tetrazóis/uso terapêutico , Adulto , Cilostazol , Análise Custo-Benefício , Método Duplo-Cego , Custos de Medicamentos , Humanos , Estudos Multicêntricos como Assunto , Inibidores da Agregação Plaquetária/economia , Ensaios Clínicos Controlados Aleatórios como Assunto , Tetrazóis/economia , Fatores de Tempo , Resultado do Tratamento
13.
Am J Cardiol ; 98(5): 649-52, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16923454

RESUMO

Elevated blood pressure (BP) variability has been linked to an increased risk for adverse cardiovascular events, but the biologic factors that promote elevated BP variability are not entirely understood. This cross-sectional study examined whether inflammatory factors might be associated with elevated BP variability during 24-hour ambulatory BP monitoring. Subjects were 140 healthy, normotensive adults. Inflammatory markers included C-reactive protein (CRP) and tumor necrosis factor-alpha. BP variability was calculated as the within-subject SD of BP values obtained during the daytime, nighttime, and 24-hour periods. In linear regression models that were adjusted for mean BP and other factors, CRP quartiles were positively associated with daytime systolic BP variability; for subjects in the lowest to highest CRP quartiles, the mean within-subject SDs of daytime systolic BP were 9.31, 9.62, 10.55, and 11.17, respectively (p for linear trend = 0.001). CRP showed similar positive associations with nighttime and 24-hour systolic BP variability. In contrast, tumor necrosis factor-alpha was not independently associated with systolic BP variability during any of the time periods. With respect to diastolic BP variability, significant positive associations were found between CRP and diastolic BP variability during all time periods and between tumor necrosis factor-alpha and daytime diastolic BP variability. In conclusion, there are positive associations between markers of inflammation and BP variability in healthy, normotensive adults, suggesting that inflammation may be 1 of the factors that promotes increased BP variability.


Assuntos
Biomarcadores/sangue , Pressão Sanguínea/fisiologia , Proteína C-Reativa/metabolismo , Ritmo Circadiano/fisiologia , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Monitorização Ambulatorial da Pressão Arterial , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência
14.
Endocrinology ; 146(8): 3343-50, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15890771

RESUMO

We generated a Spot 14 null mouse to assess the role of Spot 14 in de novo lipid synthesis and report the Spot 14 null mouse exhibits a phenotype in the lactating mammary gland. Spot 14 null pups nursed by Spot 14 null dams gain significantly less weight than wild-type pups nursed by wild-type dams. In contrast, Spot 14 null pups nursed by heterozygous dams show similar weight gain to wild-type littermates. We found the triglyceride content in Spot 14 null milk is significantly reduced. We demonstrate this reduction is the direct result of decreased de novo lipid synthesis in lactating mammary glands, corroborated by a marked reduction of medium-chain fatty acids in the triglyceride pool. Importantly, the reduced lipogenic rate is not associated with significant changes in the activities or mRNA of key lipogenic enzymes. Finally, we report the expression of a Spot 14-related gene in liver and adipose tissue, which is absent in the lactating mammary gland. We suggest that expression of both the Spot 14 and Spot 14-related proteins is required for maximum efficiency of de novo lipid synthesis in vivo and that these proteins impart a novel mechanism regulating de novo lipogenesis.


Assuntos
Lactação/fisiologia , Lipídeos/biossíntese , Glândulas Mamárias Animais/fisiologia , Proteínas/genética , Acetil-CoA Carboxilase/metabolismo , Sequência de Aminoácidos , Animais , Feminino , Camundongos , Camundongos Knockout , Leite/química , Proteínas do Leite/análise , Dados de Sequência Molecular , Proteínas Nucleares , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Fatores de Transcrição
15.
Dev Comp Immunol ; 29(6): 565-82, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15752552

RESUMO

Recently, we have shown that exposure of fetal thymus organ cultures (FTOC) to modeled microgravity (MMG) using a clinostat with a microgravity organ culture dish system (MOCDS) blocks T cell development in a manner independent of steroid stress hormones present in vivo. In this study, we describe the development of the MOCDS system, as well as its use in attempting to understand the mechanism by which T cell development is inhibited in MMG. We show that after MMG exposure FTOC exhibited a significant reduction in CD4+CD8+ double positive (DP) cell production, but those DP cells which remained expressed higher levels of the T cell receptor (TCR) associated molecule, CD3. Interestingly, CD4-CD8- double negative (DN) cells expressed lower levels of CD3 on their surface. DN, as well as immature single positive (ISP) cells, also expressed reduced levels of the IL-7 receptor alpha chain (CD127). These changes in CD3 and CD127 expression were concomitantly associated with an increased production of tumor necrosis factor (TNF)-alpha. We were also able to show that addition of an exogenous signal (anti-CD3epsilon monoclonal antibody) to these cultures effectively mitigated the MMG-induced effects, suggesting that MMG-exposure causes a signal dampening effect on developing thymocytes.


Assuntos
Desenvolvimento Fetal/imunologia , Técnicas de Cultura de Órgãos/métodos , Linfócitos T/imunologia , Timo/imunologia , Simulação de Ausência de Peso/métodos , Animais , Complexo CD3/imunologia , Feminino , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Receptores de Interleucina-7/imunologia , Organismos Livres de Patógenos Específicos , Subpopulações de Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/imunologia , Simulação de Ausência de Peso/instrumentação
16.
Endocrinology ; 144(12): 5242-8, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12960053

RESUMO

Spot 14 is a 17-kDa protein expressed in lipogenic tissues and is postulated to play a role in thyroid hormone stimulation of lipogenesis. To further our understanding of Spot 14 regulation in humans, our laboratory recently cloned the human Spot 14 gene. The gene is highly homologous to the rat Spot 14 ortholog and located on a chromosomal region implicated in human obesity. Because our understanding of Spot 14 transcriptional regulation is derived from rat promoter studies, we assessed the thyroid hormone responsivity of the human Spot 14 promoter. These studies revealed a significantly greater thyroid hormone response for the human promoter, compared with the rat. Deletional studies of the human Spot 14 promoter reveal a 774-bp region at approximately position -2700, which is both necessary and sufficient for the thyroid hormone response. EMSAs with subfragments from this region identify a 146-bp DNA fragment capable of binding a TRbeta1-retinoid X receptor heterodimer. Site-directed mutagenesis confirmed the identity of a candidate DR-4 thyroid hormone response element within this fragment that is similar, but not identical, to the two rat Spot 14 thyroid hormone response elements. We hypothesize that the difference in thyroid hormone response between the orthologous promoters may allow a selective advantage to each species based on their different nutritional and physiological niches.


Assuntos
Glucose/farmacologia , Proteínas/genética , Proteínas/metabolismo , Hormônios Tireóideos/farmacologia , Animais , Células Cultivadas , Hepatócitos/citologia , Humanos , Masculino , Mutagênese/fisiologia , Proteínas Nucleares , Regiões Promotoras Genéticas/fisiologia , Ratos , Ratos Sprague-Dawley , Elementos de Resposta/genética , Especificidade da Espécie , Fatores de Transcrição , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/fisiologia
17.
Endocrinology ; 145(11): 5013-20, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15256491

RESUMO

Thyroid hormone (TH) is necessary for normal axonal myelination. Myelin basic protein (MBP) is a structural protein essential for myelin function. In this study, we demonstrate that perinatal hypothyroidism regulates MBP mRNA levels via indirect mechanisms. We observed decreased MBP mRNA accumulation in the hypothyroid rat brain at postnatal (PN) d 10 and 50. Acute TH replacement did not rescue hypothyroid MBP mRNA levels at PN5, 10, or 50. TH is necessary for normal intrahemispheric commissure development including the anterior commissure (AC) and the corpus callosum (CC). We determined that perinatal hypothyroidism decreases AC area and cellularity in the developing rat brain by PN10 and 50. In the developing CC, hypothyroidism initially increases area and cellularity by PN5, but then ultimately decreases area and cellularity by PN50. MBP-expressing oligodendrocytes are a recognized target of TH and are responsible for myelination within intrahemispheric commissures. We found that hypothyroidism reduces the number of mature oligodendrocytes within both the AC and CC. This reduction is noted at PN5, 10, and 50 in the AC and by PN10 and 50 in the CC. Together, these data suggest that TH regulates MBP mRNA levels through indirect mechanisms. These data demonstrate the complex mechanisms whereby TH regulates myelination in the developing brain.


Assuntos
Corpo Caloso/citologia , Hipotireoidismo/fisiopatologia , Fibras Nervosas Mielinizadas/fisiologia , Oligodendroglia/citologia , Hormônios Tireóideos/fisiologia , Animais , Contagem de Células , Corpo Caloso/crescimento & desenvolvimento , Corpo Caloso/fisiologia , Proteína Básica da Mielina/genética , Bainha de Mielina/fisiologia , Oligodendroglia/fisiologia , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley
18.
Mol Cell Endocrinol ; 199(1-2): 49-60, 2003 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-12581879

RESUMO

Thyroid hormone plays an important role in oligodendrocyte development. The studies presented here suggest that thyroid hormone is required for oligodendrocyte survival during development. Oligodendrocyte precursor cells, astrocytes and microglia were cultured in a defined media. Oligodendrocyte precursor cell differentiation was induced by growth factor removal. Time course studies revealed that oligodendrocytes cultured in the presence or absence of triiodothyronine (T3) develop similarly during the first 3 days of development. Oligodendrocytes cultured in the absence of T3, however, die after developmental day 3. TdT-Mediated dUDP Nick End Labeling assay and Hoechst staining indicate that T3 rescues developing oligodendrocytes from death by apoptosis. Apoptosis is likely induced by the presence of the cytokines TNFalpha and IL-1beta. However, expression of these cytokines is not altered by thyroid hormone administration. Thus, thyroid hormone has been demonstrated to effect proliferation, myelin gene expression and now the survival of developing oligodendrocytes.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Oligodendroglia/citologia , Tri-Iodotironina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Técnicas de Cocultura , Relação Dose-Resposta a Droga , Interleucina-1/biossíntese , Neuroglia/citologia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Tri-Iodotironina/análogos & derivados , Fator de Necrose Tumoral alfa/biossíntese
19.
Int J Dev Neurosci ; 21(5): 267-75, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12850060

RESUMO

Hypothyroidism in early postnatal development leads to abnormal CNS development that may be controlled in part at the level of gene transcription. Comparing the expression of euthyroid (EuT) and hypothyroid (HypoT) rat brain mRNAs by differential display PCR (ddPCR), we identified a novel dynamin III mRNA that was up-regulated in the hypothyroid state. Northern analysis of brain mRNA using a probe from the dynamin III open reading frame (ORF) revealed two transcripts of 3.0 and 7.2kb size. The 3.0 kb transcript was observed in testis and brain, but not liver or lung RNA. In the brain the 3.0 kb transcript increased from 25 to 57% of adult (Ad) levels from postnatal day (p) p2-p15, but was not significantly regulated by thyroid hormone status. In contrast, the more abundant 7.2 kb transcript increased from 16.8 to 48.0% of adult levels from p2 to p15 in euthyroid rat pups but from 54.0% of adult levels at p2 to 97.9% of adult levels by p15 in hypothyroid pups. Overlapping cDNA clones from a rat brain cDNA library defined the 7.2kb mRNA, which consisted of the complete ORF, containing a four amino acid insert at the end of the pleckstrin homology domain (PHD), and two unique 3'-flanking regions, that are likely derived from alternative processing. Thus, the 7.2 kb dynamin III transcript is brain-specific and selectively regulated by thyroid hormone status. The data suggest that the regulation of dynamin III by altered thyroid hormone status may affect synaptogenesis in the CNS through dynamin's essential roles in synaptic vesicle and receptor recycling, neurotransmitter reuptake, and growth factor receptor signaling.


Assuntos
Sistema Nervoso Central/metabolismo , Dinamina III/metabolismo , Hipotireoidismo/metabolismo , Sequência de Aminoácidos , Animais , Northern Blotting , Dinamina III/genética , Feminino , Perfilação da Expressão Gênica , Biblioteca Gênica , Fígado/metabolismo , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Isoformas de Proteínas , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Testículo/metabolismo , Regulação para Cima
20.
Thyroid ; 13(11): 1039-56, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14651788

RESUMO

Thyroid hormones play important roles in brain development. The physiologic function of thyroid hormones in the developing brain is to provide a timing signal that leads to the induction of differentiation and maturation programs during precise stages of development. Inappropriate initiation of these timing events leads to asynchrony in developmental processes and a deleterious outcome. The developing brain is protected from premature thyroid hormone signaling through a variety of measures. Firstly, local brain levels of both thyroxine and triiodothyronine are controlled by ontogenically regulated patterns of production and metabolism. Secondly, developmentally regulated expression of nuclear proteins involved with the nuclear TH response apparatus control the temporal response of brain genes to thyroid hormone. Finally, developmental regulation of TH action modulating transcription factor expression also controls TH action in the developing brain. Together these molecular mechanisms cooperatively act to temporally control TH action during brain development. A description of these controlling mechanisms is the subject of this review.


Assuntos
Encéfalo/crescimento & desenvolvimento , Hormônios Tireóideos/fisiologia , Envelhecimento/fisiologia , Animais , Encéfalo/citologia , Encéfalo/embriologia , Diferenciação Celular , Núcleo Celular/enzimologia , Desenvolvimento Embrionário e Fetal , Ratos , Transdução de Sinais , Tirosina 3-Mono-Oxigenase/metabolismo
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